1. Field of the Invention
This invention relates to a method of filling bags such as sacks which define at least one opening at one end and an apparatus for carrying out the inventive method.
2. Description of the Prior Art
Rotary packers often comprise a number of filling spouts from which the sacks are suspended, or beneath which the sacks are placed and supported by means of a sack bracket, during filling. The filling spouts are usually uniformly distributed in a circle and rotated about the verticle axis of the packer. The empty sacks are usually placed manually on the filling spouts by an operator whose only task is to pick an empty sack from a sack magazine and to place the empty sack on an empty filling spout as it passes him. All other operations of the packing machine, including filling of the sack, usually to a predetermined weight, and the discharge and removal of the filled sacks, are automatic.
It is also known to automate the manual operation by providing a gripping mechanism adapted to take one empty sack at a time from the sack magazine and to open the valve opening of the sack on or opposite an empty filling spout. The automation for this particular purpose is, however, highly complicated and requires much space as well as being costly as an initial investment and in its operation.
Swiss Pat. No. 240,697 relates to an apparatus for filling powdered material into containers. Powdered material is lifted by stirring elements from the bottom of a material supply tank up to its top edge. This material leaves the tank in the form of a number of jets through outlet connections which also serve as attachments for the containers into which the material flows. The containers are placed on the outlet connections manually and removed manually after being filled to a predetermined weight.
U.S. Pat. No. 1,903,188 to Middelboe relates to a machine for filling valve bags with a definite weight of pulverous material. A filling tank rotatably arranged about a vertical axis is combined with a number of filling spouts which extend from the lower part of the filling tank. The filling spouts are adapted to serve as a carrier and feeding device for the valve bags which are attached thereto by an operator, and each spout is supplied with a flow cut-off mechanism controlled by a weighing mechanism.
German Pat. No. 1,255,562 relates to a packing machine for filling bulk material into bags which has a device for feeding bags from a magazine to a filler cap. This feeding device consists of a frame rigidly connected to the packing unit. The frame carrier has a guide bar arranged in a plane located above both the filler cap and a magazine which is spaced a certain distance away from the rotary packer. A truck having a catch to engage the top bag in the magazine moves back and forth on this guide between the bag magazine and a filler spout.
According to my invention material is introduced into bags such as sacks in a manner which provides a substantial saving in time. The preferred arrangement is fully automatic thereby rendering the manual operation in placing of the sacks on the filling spouts superfluous. Further, the fully automatic plant is uncomplicated, requires limited space, and has a low primary cost and low cost of operation.